You need firstly have to install the requirments for compile the BOINC client : http://boinc.berkeley.edu/trac/wiki/SoftwarePrereqsUnix
Then port the BOINC client : http://boinc.berkeley.edu/trac/wiki/CompileClient BOINC client, lib and api would be needed primarly before you can port the SETI application. BOINC Graphics and client GUI is optional.

I recommend you to compile gmake from www.gnu.org. The error messages looks like awk is also missing. You can also compile it from GNU, if it is not installed from the OS.
Btw. I recommend you to check out the stable BOINC source, like 5.10.45 or 6.2.15. You can check out the svn with : svn co http://boinc.berkeley.edu/svn/tags/boinc_core_release_5_10_45